Among Trans-Himalayan valleys with cold desert climate, surface melt water runoff noticed in the winter months of November to February. This melt water is being used for feeding artificial glaciers(water storage technique, ref: http://icestupa.org/).

1) I would like to know how there is glacier melt water runoff in the subzero temperatures of winter season, at an altitude of >3500m AMSL?

2) (As a non-glaciologist), I came across certain terminologies namely En-glacial flow, Sub-glacial flow and Base-flow where ice melts due to geothermal activity or pressure melting or friction melting. These flow pathways act as water drainage pathways from glaciers.

Kindly provide hints on winter Surface runoff prediction based on the respective glacier classification?

3)And further, is there any research on spatial map of glacier classification (as Cold, Temperate and Polythermal) in Trans-Himalayan region, which can indicate the availability of winter melt water runoff?

Kindly provide supportive reference research to help me understand the concepts.

Thank you